JP2022178346A - Sheet-like molding material, molded body and manufacturing method of them - Google Patents

Abstract

To provide a molding material, etc. capable of manufacturing a molded body using lacquer which has a thinner thickness.SOLUTION: A manufacturing method of a sheet-like molding material includes the steps of: impregnating a sheet-like base material containing vegetable fibers with lacquer to obtain a lacquer-contained sheet-like base material; and heating the lacquer-contained sheet-like base material to obtain the sheet-like molding material.SELECTED DRAWING: Figure 1

Description

TECHNICAL FIELD The present invention relates to a sheet-like molding material, a molded article, and a method for producing these.

Lacquer is sap exuded from lacquer trees, and lacquerware coated with lacquer is used as tableware, furniture, crafts, and the like. In recent years, many products made of synthetic resin have been used instead of lacquerware, but there is a suspicion that some of these products contain substances that are harmful to the human body.

Therefore, for the purpose of expanding the use of lacquer and providing a product that does not adversely affect the human body, Patent Document 1 discloses a compact obtained by compression-molding a powder material obtained from lacquer and plant fibers. It discloses that it forms a Specifically, Patent Document 1 discloses that ``lacquer and vegetable fibers are blended in a weight ratio of 1:9 to 6:4, kneaded, and heated at a temperature of 90 to 180°C for 30 to 120 minutes while stirring. The urushiol is partially thermally polymerized at a temperature of between 120° C. and Lacquer/vegetable fiber compression molding obtained by compression molding at a pressure of 15 to 40 MPa.”.

In addition, Patent Document 2 describes, for the purpose of improving the powder material and molded body of Patent Document 1, "powder molding obtained by three-dimensionally kneading lacquer and vegetable fibers while heating. material" and compacts obtained by compression-molding said material.

Patent No. 3779290 specification Patent No. 6140607

When using the powder materials disclosed in Patent Documents 1 and 2, there is a problem that it is difficult to produce a thin plate-like compression-molded body having a thickness of about 1 to 2 mm. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a molding material or the like from which a molded product using lacquer having a small thickness can be produced.

As a result of intensive studies by the present inventors, the inventors have found that the desired molding material can be obtained by impregnating a sheet-like substrate containing plant fibers with Japanese lacquer and heating it, thus completing the present invention. rice field.

The present invention includes the following embodiments.
[1]
A step of impregnating a sheet-like base material containing plant fibers with lacquer to obtain a lacquer-containing sheet-like base material;
a step of heating the lacquer-containing sheet-like substrate to obtain a sheet-like molding material;
A method for producing a sheet-like molding material, comprising:
[2]
The production method according to [1], wherein the sheet-like substrate has a thickness of 0.1 to 2.0 mm.
[3]
The production method according to [1] or [2], wherein the sheet-like substrate has a density of 0.10 to 0.85 g/cm ³ .
[4]
The amount of the lacquer contained in the lacquer-containing sheet-like substrate is 30 to 70% by mass based on the weight of the lacquer-containing sheet-like substrate, according to any one of [1] to [3]. Production method.
[5]
The production method according to any one of [1] to [4], wherein the heating of the lacquer-containing sheet-like substrate partially cures the lacquer contained in the lacquer-containing sheet-like substrate.
[6]
The production method according to any one of [1] to [5], wherein the heating of the lacquer-containing sheet-like substrate is carried out at 90 to 180°C.
[7]
The production method according to any one of [1] to [6], wherein the heating of the lacquer-containing sheet-like substrate is performed for 30 to 360 minutes.
[8]
A step of compression molding a sheet-shaped molding material produced by the production method according to any one of [1] to [7];
A method for producing a molded body, comprising:
[9]
The production method according to [8], wherein the compression molding is performed at 120 to 180°C.
[10]
The production method according to [8] or [9], wherein the compression molding is performed by laminating two or more sheets of the sheet-like molding material.
[11]
a step of applying lacquer to the surface of the molded body;
The production method according to any one of [8] to [10], further comprising
[12]
a step of heating the molded body to completely harden the lacquer;
The production method according to any one of [8] to [11], further comprising
[13]
a sheet-like base material containing vegetable fibers;
Lacquer impregnated in the sheet-like base material;
including
The lacquer is partially cured,
Sheet molding material.
[14]
The sheet-like molding material according to [13], wherein the sheet-like molding material consists only of the vegetable fibers and the lacquer.
[15]
The sheet-shaped molding material according to [13] or [14], wherein the sheet-shaped molding material has a thickness of 0.1 to 2.0 mm.
[16]
[13] A molded product which is a compression molded product of the sheet-like molding material according to any one of [13] to [15].
[17]
The molded article according to [16], wherein two or more sheets of the sheet-like molding material are laminated and compressed.
[18]
The molded article according to [16] or [17], wherein the molded article has a thickness of 0.1 mm or more.

ADVANTAGE OF THE INVENTION According to this invention, the molding material etc. which can manufacture the molded object using lacquer|lacquer with thin thickness can be provided.

FIG. 1 shows the maximum stress of Examples 1 to 5 and comparative molded articles (thickness of filter paper: 0.8 mm) in which the amount of lacquer impregnated was varied. FIG. 2 shows the elastic moduli of Examples 1 to 5 and comparative molded articles (thickness of filter paper: 0.8 mm) in which the amount of lacquer impregnated was varied. FIG. 3 shows the maximum stress of Examples 6 and 7 with different heat treatment times after impregnation with Japanese lacquer, and the comparative molded body (thickness of filter paper: 0.34 mm). FIG. 4 shows the elastic moduli of Examples 6 and 7 with different heat treatment times after impregnation with Japanese lacquer, and the comparative molded article (thickness of filter paper: 0.34 mm). FIG. 5 shows the maximum stress of Examples 8 to 10 and comparative molded bodies (thickness of filter paper: 0.8 mm) with different heat treatment times after lacquer impregnation. FIG. 6 shows the elastic moduli of Examples 8 to 10 and comparative molded bodies (thickness of filter paper: 0.8 mm) in which the heat treatment time after lacquer impregnation was varied. FIG. 7 shows the maximum stress of Examples 11 and 12 with different heat treatment times after impregnation with Japanese lacquer, and the comparative molded body (thickness of filter paper: 1.2 mm). FIG. 8 shows the elastic moduli of Examples 11 and 12 with different heat treatment times after impregnation with Japanese lacquer, and the comparative molded body (thickness of filter paper: 1.2 mm). FIG. 9 shows the maximum stress of the laminated molded bodies (filter paper thickness: 0.8 mm) of Examples 1A to 5A with varying amounts of impregnated lacquer. FIG. 10 shows the elastic moduli of the laminate molded bodies (filter paper thickness: 0.8 mm) of Examples 1A to 5A with different lacquer impregnation amounts. FIG. 11 shows the maximum stress of the laminated molded bodies (filter paper thickness: 0.8 mm) of Examples 8A and 9A with different heat treatment times after lacquer impregnation. FIG. 12 shows the elastic moduli of the laminated molded bodies (filter paper thickness: 0.8 mm) of Examples 8A and 9A with different heat treatment times after lacquer impregnation. FIG. 13 shows the maximum stress of the laminate molded bodies (filter paper thickness: 1.2 mm) of Examples 11A and 12A with different heat treatment times after impregnation with Japanese lacquer. FIG. 14 shows the elastic moduli of the laminate molded bodies (filter paper thickness: 1.2 mm) of Examples 11A and 12A with different heat treatment times after lacquer impregnation.

Embodiments of the present invention will be specifically described below, but the present invention is not limited to these, and various modifications are possible without departing from the scope of the invention.

<Method for manufacturing sheet-shaped molding material>
One embodiment of the present invention comprises a step of impregnating a sheet-like substrate containing plant fibers with lacquer to obtain a lacquer-containing sheet-like substrate (hereinafter referred to as an "impregnation step"), and the lacquer-containing sheet-like substrate. to obtain a sheet-like molding material (hereinafter referred to as "heating step").

In the manufacturing method according to the present embodiment, the sheet-like base material is impregnated with Japanese lacquer and heated (cured by thermal polymerization) to obtain a molding material that can be used to manufacture a thin molded body. Also, by using the molding material, it is possible to improve the durability of the molded product.

Although the following reasons can be assumed for the ability to produce a molded article having a small thickness and excellent durability, the present invention is not limited by the reasons assumed below.
That is, in the powder material disclosed in Patent Document 1, the vegetable fibers are cut short during pulverization, so the entanglement of the vegetable fibers is reduced and the durability is reduced. The plant fibers that make up the sheet-like base material used have relatively long fiber lengths and are entangled with each other, so it is assumed that the durability can be maintained even if the thickness is reduced.

[Impregnation process]
The impregnation step is a step of impregnating a sheet-like base material containing plant fibers with lacquer to obtain a lacquer-containing sheet-like base material. The method of impregnating the lacquer is not particularly limited, and examples thereof include a method of applying lacquer to the sheet-like substrate and a method of immersing the sheet-like substrate in lacquer.

The thickness of the sheet-like substrate is preferably 0.1 to 2.0 mm, more preferably 0.2 to 1.7 mm, still more preferably 0.3 to 1.4 mm. By setting the thickness of the sheet-like substrate within the above range, the sheet-like substrate can be uniformly impregnated with lacquer.

The density of the sheet-like substrate is preferably 0.10 to 0.85 g/cm ³ , more preferably 0.25 to 0.70 g/cm ³ , still more preferably 0.40 to 0.55 g/cm 3 . ^cm3 . By setting the density of the sheet-like substrate within the above range, the sheet-like substrate can be uniformly and sufficiently impregnated with lacquer.

The plant fibers constituting the sheet-like substrate are not particularly limited, but examples include plant fibers derived from cedar, cypress, hemlock, paulownia, pine, spruce, bamboo, reed, cotton, and the like. Plant fibers may be used singly or in combination of two or more. Although not particularly limited, the sheet-like base material is preferably composed only of plant fibers, and more preferably composed only of cellulose.

The type of lacquer is not particularly limited, and examples thereof include lacquer obtained from lacquer trees produced in Japan, lacquer trees produced in China, lacquer trees produced in Taiwan, lacquer trees produced in Vietnam, lacquer trees produced in Thailand, and lacquer trees produced in Myanmar. The main components of lacquer vary depending on the lacquer tree, but examples include urushiol, laccol, and thithiol. Regardless of which component is lacquer as the main component, it can be used in the manufacturing method according to the present embodiment. Lacquer may be used individually by 1 type, and may be used in combination of 2 or more type.

The amount of lacquer contained in the lacquer-containing sheet-like substrate is preferably 30 to 70% by mass, more preferably 48 to 68% by mass, and still more preferably, based on the mass of the lacquer-containing sheet-like substrate. 58 to 68% by mass. By setting the amount of lacquer to 30% by mass or more, the sheet-like substrate can be uniformly impregnated with lacquer. By setting the amount of lacquer to 70% by mass or less, elution of lacquer from the sheet-like substrate can be suppressed.

[Heating process]
The heating step is a step of heating the lacquer-containing sheet-like substrate to obtain a sheet-like molding material. By heating the lacquer-containing sheet-like substrate, the laccase contained in the lacquer can be deactivated, and the curing (thermal polymerization) of the lacquer by heating can proceed. Laccase causes oxidative polymerization of lacquer, but the degree of oxidative polymerization is greatly affected by storage time, temperature and humidity, and composition of lacquer. It is difficult to keep Quality can be stabilized by deactivating the laccase and using thermal polymerization instead.

The heating method is not particularly limited, and examples thereof include heating the lacquer-containing sheet-like substrate with a hot air dryer. Although the sheet-like molding material is dry to the touch at room temperature, it is preferable to heat the lacquer-containing sheet-like base material to such an extent that it softens under the conditions of the following forming step.

In the heating step, it is preferable to partially cure the lacquer contained in the lacquer-containing sheet-like substrate. Since the lacquer is partially cured (in other words, the lacquer is partially uncured), the lacquer-containing sheet-like substrate is moderately softened when compressed in the subsequent molding process, so the molding is performed. easier to do. Moreover, since the lacquer is partially cured, the curing time in the forming process can be shortened. Furthermore, since the lacquer is partially uncured, when two or more sheet-shaped molding materials are laminated and compression-molded in the following molding process, a molded body in which the sheet-shaped molding materials are bonded and integrated is formed. Obtainable. As a method to confirm that the lacquer is partially cured, for example, eluting uncured lacquer with acetone, or observing the peak derived from the double bond of the main component of lacquer by infrared spectroscopy. method.

The heating temperature is preferably 90 to 180°C, more preferably 100 to 160°C, still more preferably 110 to 140°C. By setting the heating temperature to 90° C. or higher, the laccase can be sufficiently deactivated and the thermal polymerization can be sufficiently advanced. By setting the heating temperature to 180° C. or lower, excessive thermal polymerization can be suppressed and ignition due to heat generation can be avoided.

The heating time may be appropriately adjusted according to, for example, the thickness of the sheet-like substrate and the amount of impregnated lacquer. For example, the heating time may be 30-360 minutes, 60-360 minutes, or 120-360 minutes.

<Method for manufacturing molded body>
One embodiment of the present invention relates to a method for producing a molded body, which includes a step of compression-molding the sheet-shaped molding material produced by <Method for producing sheet-shaped molding material> (hereinafter referred to as “forming step”).

The method of compression molding is not particularly limited, and for example, a method of placing a sheet-like molding material in a mold having a desired shape and compressing it can be mentioned. Examples of the mold include a metal sheet mold and an embossing mold.

In the production method according to the present embodiment, a compact having a small thickness can be produced by using a sheet-shaped molding material. Also, by using a sheet-like molding material, it is possible to improve the durability of the molded product.

The compression molding temperature is preferably 120-180°C, more preferably 140-160°C. By setting the compression molding temperature to 120° C. or higher, poor curing can be avoided and molding time can be shortened. By setting the compression molding temperature to 180°C or less, it is possible to avoid the situation in which the molded body is completely cured before being molded into the desired shape, and the generation of gas causes a part of the molded body to expand. situation can be avoided.

The compression molding pressure may be appropriately adjusted according to, for example, the thickness and shape of the molded body. For example, the compression molding pressure may be 1-20 MPa, 2-14 MPa, or 4-8 MPa.

In the molding step, one sheet-like molding material may be compression-molded, or two or more sheet-like molding materials may be laminated and compression-molded. A material different from the sheet-like forming material according to the present embodiment may be laminated with the sheet-like forming material (including a mode in which the different material is sandwiched between the sheet-like forming materials) and compression-molded.

The method for producing a molded article according to the present embodiment may further include a step of applying lacquer to the surface of the molded article obtained in the molding step (hereinafter referred to as "coating step"). Since the sheet-like molding material used for manufacturing the molded article contains lacquer, the molded article has a property of being easily compatible with lacquer. Therefore, in the coating process, it is possible to omit the surface treatment that is generally performed before applying lacquer.

The method for manufacturing a molded article according to the present embodiment may further include a step of heating the molded article (hereinafter referred to as a "final heating step") after the molding step or the coating step. It is preferable that the lacquer contained in the molded article (including the lacquer applied to the surface of the molded article) be completely cured by the final heating step. As a result, for example, it is possible to improve the adhesion between the surface of the molded article and the lacquer applied to the surface, and to reduce the possibility of lacquer rash when using the molded article.

<Sheet-shaped molding material>
One embodiment of the present invention relates to a sheet-like molding material comprising a sheet-like base material containing plant fibers and lacquer impregnated in the sheet-like base material, wherein the lacquer is partially cured. . The details of the sheet-like base material and lacquer are as described in <Method for producing sheet-like molding material> above.

The sheet-shaped molding material according to the present embodiment is easy to mold because the lacquer is partially uncured and moderately softened during compression molding. In addition, since the lacquer is partially cured, the curing time during compression molding can be shortened.

It is preferable that the sheet-like molding material according to the present embodiment is composed only of vegetable fibers and lacquer. The vegetable fiber is preferably cellulose only.

The thickness of the sheet-shaped molding material according to this embodiment is not particularly limited, but may be, for example, 0.1 to 2.0 mm, 0.2 to 1.8 mm, or 0.3 to 1.7 mm. By reducing the thickness of the sheet-shaped molding material according to this embodiment, the thickness of the molded product can also be reduced.

The amount of lacquer contained in the sheet-shaped molding material according to the present embodiment is preferably 20 to 65% by mass, more preferably 40 to 60% by mass, and still more preferably, based on the mass of the sheet-shaped molding material. is 50 to 60% by mass. By setting the amount of lacquer to 20% by mass or more, a sheet-shaped molding material uniformly impregnated with lacquer can be obtained. By setting the amount of lacquer to 65% by mass or less, the elution of lacquer from the sheet-shaped molding material can be suppressed, and the stickiness of the surface of the sheet-shaped molding material can be suppressed.

<Molded body>
One embodiment of the present invention relates to a compact that is a compression-molded product of the <sheet-shaped molding material>. The molded article according to this embodiment can maintain durability while reducing the thickness.

The compact according to the present embodiment may be a compression-molded product of one sheet-shaped molding material, or may be a compression-molded product of laminated two or more sheet-shaped molding materials. The molded product according to the present embodiment may be a compression molded product of a laminated sheet-like forming material and a material different from the sheet-like forming material.

The thickness of the molded body according to this embodiment is not particularly limited, but may be, for example, 0.1 mm or more, 0.1 to 10 mm, or 0.1 to 1.5 mm. The thickness of the molded body can be reduced, for example, by reducing the thickness of the sheet-like molding material. The thickness of the molded body can be increased, for example, by increasing the thickness of the sheet-shaped molding material or by laminating the sheet-shaped molding material.

EXAMPLES The present invention will be described in more detail below using examples and comparative examples, but the technical scope of the present invention is not limited thereto.

<Example 1>
Chinese lacquer (main component: urushiol) was applied to a pure cellulose filter paper (GB003 manufactured by Global Life Science Technologies Japan Co., Ltd.) with a thickness of 0.8 mm made only of cotton linter (fiber material remaining in seeds after cotton is harvested). was impregnated so that the content ratio (based on the mass of the lacquer-containing sheet-like substrate) shown in Table 1 was obtained, to obtain a lacquer-containing sheet-like substrate. The lacquer-containing sheet-like substrate was heated at 120° C. for 4 hours to obtain a sheet-like molding material.

The resulting sheet-like molding material was compression molded for 1 hour at 150° C. and 6 MPa using a hot press. After compression molding, it was heated at 150° C. for 24 hours to obtain a molded body.

<Examples 2 to 5>
A compact was obtained in the same manner as in Example 1, except that the lacquer impregnation ratio was changed as shown in Table 1.

In the production of the molded bodies, the molded bodies of Examples 1 and 2 were slightly warped, but no major problems occurred. In Example 5, lacquer seeped out from the surface of the molded article, but no major problems occurred. No abnormalities were observed in Examples 3 and 4.

<Example 6>
A 0.34 mm thick pure cellulose filter paper (3MM Chr manufactured by Global Life Science Technologies Japan Co., Ltd.) made only of cotton linter was added with Chinese lacquer (main component: urushiol), and the content ratio shown in Table 2 (lacquer-containing sheet Based on the mass of the base material), a lacquer-containing sheet-like base material was obtained. The lacquer-containing sheet-like substrate was heated at 120° C. for 2 hours to obtain a sheet-like molding material.

The resulting sheet-like molding material was compression molded for 1 hour at 150° C. and 6 MPa using a hot press. After compression molding, it was heated at 150° C. for 24 hours to obtain a molded body.

<Example 7>
A compact was obtained in the same manner as in Example 6, except that the heat treatment time after impregnation with lacquer was changed to 4 hours.

<Example 8>
Chinese lacquer (main component: urushiol) was added to a 0.8 mm thick pure cellulose filter paper (GB003 manufactured by Global Life Science Technologies Japan Co., Ltd.) made only of cotton and linter, and the content ratio shown in Table 2 (lacquer-containing sheet form Based on the mass of the base material), a lacquer-containing sheet-like base material was obtained. The lacquer-containing sheet-like substrate was heated at 120° C. for 2 hours to obtain a sheet-like molding material.

The resulting sheet-like molding material was compression molded for 1 hour at 150° C. and 6 MPa using a hot press. After compression molding, it was heated at 150° C. for 24 hours to obtain a molded body.

<Examples 9 and 10>
Molded bodies were obtained in the same manner as in Example 8, except that the heat treatment times after impregnation with lacquer were changed to 4 hours and 6 hours, respectively.

<Example 11>
Chinese lacquer (main component: urushiol) was added to a 1.2 mm thick pure cellulose filter paper (GB005 manufactured by Global Life Science Technologies Japan Co., Ltd.) made only of cotton linter, and the content ratio shown in Table 2 (lacquer-containing sheet form Based on the mass of the base material), a lacquer-containing sheet-like base material was obtained. The lacquer-containing sheet-like substrate was heated at 120° C. for 4 hours to obtain a sheet-like molding material.

The resulting sheet-like molding material was compression molded for 1 hour at 150° C. and 6 MPa using a hot press. After compression molding, it was heated at 150° C. for 24 hours to obtain a molded body.

<Example 12>
A compact was obtained in the same manner as in Example 11, except that the heat treatment time after impregnation with lacquer was changed to 6 hours.

In the production of the molded body, the molded body of Example 7 was somewhat warped, but no major problems occurred. In Examples 6 and 8, lacquer seeped out from the surface of the molded body, but no major problems occurred. No abnormalities were observed in Examples 9-12.

<Example 1A>
Using a three-dimensional mold (assumed to be a carton as a product) having an upper mold and a lower mold opposed thereto, two sheets of the sheet-like molding material obtained in Example 1 are stacked and heated to 150 ° C. and compression molding for 1 hour under conditions of 6 MPa to obtain a laminated molded body in which two sheet-like molding materials are integrated.

<Examples 2A to 5A, 8A, 9A, 11A and 12A>
A laminated molded body was obtained in the same manner as in Example 1A, except that the sheet-shaped molding materials were changed to those obtained in Examples 2 to 5, 8, 9, 11 and 12, respectively.

<Physical property evaluation>
Various physical properties of the molded articles obtained in the above Examples were evaluated. The evaluation method is as follows.

[Bending strength (maximum stress), elastic modulus]
A test piece (width = 10 ± 1 mm, length = 80 mm or more) is prepared using the molded body, and JIS K 7171 (2016) Plastics-How to determine bending properties-Bending strength (MPa) and elasticity A rate (GPa) was determined. The test was performed three times, and the average value of the three tests was taken as the bending strength (MPa) of the compression molded body. In this test, the distance between fulcrums was 25 mm, and the crosshead speed was 1 mm/min. As a measuring device, Autograph AG-10TD manufactured by Shimadzu Corporation was used.

The results of the molded bodies of Examples 1 to 5 are shown in FIGS. 1 and 2. FIG. These results indicate that the flexural strength and elastic modulus increase as the lacquer impregnation increases.

The results of the molded bodies of Examples 6 and 7 are shown in FIGS. 3 and 4. FIG. The results of the molded bodies of Examples 8 to 10 are shown in FIGS. 5 and 6. FIG. The results of the molded bodies of Examples 11 and 12 are shown in FIGS. 7 and 8. FIG. These results indicate that the strength is further improved by appropriately setting the heating time of the lacquer-containing sheet-like substrate.

The results of the laminate molded bodies of Examples 1A to 5A are shown in FIGS. 9 and 10. FIG. The results of the laminate molded bodies of Examples 8A and 9A are shown in FIGS. 11 and 12. FIG. The results of the laminate molded bodies of Examples 11A and 12A are shown in FIGS. 13 and 14. FIG.

<Example 13>
Chinese lacquer (main component: urushiol) is added to 0.8 mm thick pure cellulose filter paper (GB003 manufactured by Global Life Science Technologies Japan Co., Ltd.) consisting only of cotton linter, 50% by mass (lacquer-containing sheet-like base material based on the mass.) to obtain a lacquer-containing sheet-like substrate. The lacquer-containing sheet-like substrate was heated at 120° C. for 2 hours to obtain a sheet-like molding material. Three sheets of the obtained sheet-like molding material were stacked and compression-molded for 1 hour at 150° C. and 6 MPa to obtain a laminate (thickness: 2.0 mm) in which the three sheet-like molding materials were integrated. rice field.

<Comparative Example 1>
According to Example 1 of Japanese Patent No. 6140607, a compression-molded body (thickness: 2.0 mm) composed of lacquer produced in China and cedar wood powder was produced.

The moldings of Example 13 and Comparative Example 1 were subjected to an impact resistance test. The method of the impact resistance test is as follows.
The Charpy impact value was measured with reference to JIS K 7111-1 (2012) Plastics - Determination of Charpy impact properties. The test was conducted 9 times, and the average value of the 9 tests was taken as the Charpy impact value (kJ/m ² ). In this test, the test direction was edgewise (no notch), the distance between fulcrums was 62 mm, and the nominal pendulum energy was 1 J. A digital impact tester manufactured by Toyo Seiki Seisakusho Co., Ltd. was used as a measuring device.

As a result, the Charpy impact test value of the molded product of Comparative Example 1 was 2.56 kJ/m ² , while the Charpy impact test value of the molded product of Example 13 was 8.81 kJ/m ² , which is extremely high. It showed excellent strength properties.

Claims (18)

A step of impregnating a sheet-like base material containing plant fibers with lacquer to obtain a lacquer-containing sheet-like base material;
a step of heating the lacquer-containing sheet-like substrate to obtain a sheet-like molding material;
A method for producing a sheet-like molding material, comprising: The sheet-like base material has a thickness of 0.1 to 2.0 mm,
The manufacturing method according to claim 1. The sheet-like substrate has a density of 0.10 to 0.85 g/cm ³ ,
The manufacturing method according to claim 1 or 2. The amount of the lacquer contained in the lacquer-containing sheet-like substrate is 30 to 70% by mass based on the weight of the lacquer-containing sheet-like substrate.
The production method according to any one of claims 1 to 3. The heating of the lacquer-containing sheet-like substrate partially cures the lacquer contained in the lacquer-containing sheet-like substrate.
The production method according to any one of claims 1 to 4. The heating of the lacquer-containing sheet-like substrate is performed at 90 to 180 ° C.
The production method according to any one of claims 1 to 5. The heating of the lacquer-containing sheet-like substrate is performed for 30 to 360 minutes,
The production method according to any one of claims 1-6. A step of compression molding a sheet-shaped molding material produced by the production method according to any one of claims 1 to 7,
A method for producing a molded body, comprising: The compression molding is carried out at 120-180°C,
The manufacturing method according to claim 8. The compression molding is carried out by laminating two or more sheets of the sheet-like molding material,
The manufacturing method according to claim 8 or 9. a step of applying lacquer to the surface of the molded body;
further comprising
The production method according to any one of claims 8-10. a step of heating the molded body to completely harden the lacquer;
further comprising
The production method according to any one of claims 8-11. a sheet-like base material containing vegetable fibers;
Lacquer impregnated in the sheet-like base material;
including
The lacquer is partially cured,
Sheet molding material. The sheet-shaped molding material consists only of the vegetable fiber and the lacquer,
The sheet-like molding material according to claim 13. The sheet-shaped molding material has a thickness of 0.1 to 2.0 mm.
The sheet-shaped molding material according to claim 13 or 14. A molded product which is a compression molded product of the sheet-like molding material according to any one of claims 13 to 15. Two or more sheets of the sheet-like molding material are laminated and compressed,
The molded body according to claim 16. The molded body has a thickness of 0.1 mm or more,
The molded article according to claim 16 or 17.

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